This invention relates to direct contact water heating systems and processes, and more particularly to heating of water by the provision of direct contact of hot flue gases unwashed and unquenched with water-to-be-heated. The means of achieving the higher water temperatures, the means for removal of dissolved gases, and the means for providing make-up water without external source are all combined to achieve maximum thermal efficiency.
As the ready availability of energy resources dwindles, it becomes increasingly necessary to discover ways and means by which available energy resources can be conserved and more efficiently utilized. Especially in the area of industrial and commercial heating of water, as the availability and costs of fuel continues to increase, ways by which the heating of water can be made more thermodynamically and thus economically efficient are much sought after and are of utmost concern to those involved on a day-to-day basis in industry of various types. Previously known water heating devices, such as for instance, as shown in U.S. Pat. Nos. 3,204,629; 2,759,328; 1,527,740; 2,921,004; 3,291,119; 3,423,932; 2,875,749; 1,560,806; and 3,500,817, did not take the best thermodynamic advantage possible of their respective systems; nor did they produce non-corrosive hot water free of dissolved gases.